Pneumatic hammer.



, PATENTED JAN. 29, 1907. J. F. CLEMENT. PNEUMATIC HAMMER.

' APPLIGATIQNALED AlPR. l5, 1905.

2 SHEBTS S HEET 1.

PATENTED JAN. 29, 1907, J. F. CLEMENT. PNEUMATIQHAMMER. APPLICATIONFILED APR.15, 1905.

2 sums-sum 2.

uuenfoz q/vihwoua .4 r represents, '011 areduced scale, a longitudinalJOHN F. CLEMENT, OF PHILADELPHIA, PENNSYLVANIA.

PNEUMATIIQ HAMMER.

Specification of Letters Patent.

Application filed April 15,.i905. Serial No. 255,800.

To all whom it may concern:

Be it known that 1, JOHN F. CLEMENT, a citizen of the United States,residing in the city and county of Philadelphia, State. of

Pennsylvania, have invented a new and useful Pneumatic Hammer, of whichthe following is a specification. I

My invention consists of a novel construction of a pneumatic im act-toolin which the motivedlui used to drive the piston forward toward the.working tool does not ass through the main distribution-valve w ichcontrols the admission and exhaust of the motive fluid to the cylinder.

It further consists of a novel construction of a main distribution-valveand a novel arrangement of air ports and passages whereby a cushion oflive air isformed between the piston and the end of the valve adjacentthereto before the valve changes and the motive fluid is admitted tomove the piston forward.

It further consists of a novel construction of main distribution andinner and outer auxiliary valves coacting therewith;

It further consists ofnovel features of 'construetion, as will behereinafter fully set forth. I

Fi ure 1 represents a longitudinal sectiona view ofa-pneumatic toolembodying myinvention, having a portion of the casing removed forclearness of illustration.

being partlyopen. Fig. 4 represents a longituriinal-sectional'view of aportion of the tool, showingthe valve as being closed and certain; ofthe exhaust-ports open. Flg. 5

vertical section, partly broken away, showing the-ports and passagesthrough which the 'inotive fluid passes to return the piston and to's'eat the .valve.- Fig. 6 represents a perspective view of a portion ofthe casing, show ing the keyway' therein. Fig. 7 represents aperspective view'of the key. Fig. 8 repre- .jsents a bottoniplan viewofa modified form of the control-lin waive. Fig. 9 represents a --.planView, part y in section, of theh'a'ndl'evalves, showing thevalves asclosed. Fig-10 sectional plan view S m lar to howlng Fig, 2' representsa longituiinal sectionalview hav-" H the. inner regulating valve asbeing partly open. Fig. 11 repre-' valve, showing bot valves in openposition.

Similar numerals of reference indicate corresponding parts in thefigures. I 5

Referring to the drawings,.1 designates a Patented Jan. 29, 1907'.

sents a sectional lan view, of thehandlepneumatic, tool, comprising anouter casing or cylinder 2, within which is tightly fitted an innercasing 33 The outer end'of the casing is ta ered and is rovided with agroove 4, in whic one end 0 "a spring or clip is adapted to be seated,the other end of said spring con? tacting with the rivet-set 6 andholding the same in properfrelation to the casing 2. designates a handlewhich is'secured to' said cas1ng-2 by means of a key 8', which isadapted to fit a keyway or seat 9 inthe casing 2.

.10 designates a lug near the other end of the,

key 8 and having an opening 'therethrough adapted to receive a screwor'bolt 11, the threaded end 12 of which engages with a cor respondingthread in the sleeve of the handle 7. The key 8 is thicker near the lugand gradually tapers toward one end, and as the.

slot or keyway 9: corres onds thereto when the --bolt 11 is tightene'the'key 8 will be firmly wedged between the sleeve; or head.

block of the handle 'and its keyway 9, thus holding the handle at alltimes in proper relation to the cylind.er.

13 designates the inlet for the motive fluid, which is suitably threadedor otherwise adapted to "be connectedwith the baseforf the motivediuid.supply, which passes there-1 from through the port l'einto the chamberof] the bushing '15, which lattenhas an'o'pening or valve-seat 16there'through; y I

17 designates a valve ada ted tobe seated in the opening. 16,-which.is osely mounted T on a rod 18, which is connecte at one end to: a valve-rod19 and has at its other end a reg ulating-valve 20, which is normallyseated in, a recess in the valve 17. 1

. 21. designatesa shoulder on the rod 19 ,be-

tween which and the valve 20. the valve 17'is movable.v

22 designates the enlarged end or headof the valve rod :19, betweenwhich and'the inf ner wall-oflthe chamber 23 a spring 24isinterposed,"the tension of which normally keeps the valves '17 and 20closed. 25.designates a "manually-operated lever suitably pivoted-at 26and ada tedto operate the valve-rod 19 and the 'va ves actuated "thereb.

I271 designates an air passage or pressurethe inlet-port 28, which opensinto the casing times in a recess 46 in thetop of the main being smallerthan the port 57, so that'when its - the bottom of the main valve 29,which latter supply duet leading from the opening 16 to 1.

within which the main distribution-valve 29 is adapted to reciprocateand which is composed of two difi'd'ential areas 30' and 31.

he large differential area 3] is adapted to move within the'bore 32,while the small differential area 30 is adapted to move within the boreor piston-chamber 33, within which latter a piston 34 is also adapted toreciprocate.

35 designates an annular groove in the area 30 of the valve 29, and 36designates another groove in said area which extends partly into thelarger area 31. I I". 37 designates air-passages leading from the groove35 into a chamber 38. within which the two auxiliary valves 39 and 40are adapted to move. The inner auxiliary valve 39 has a reduced end orstriker o'r tappet 41, which has recesses 42 therein and is adapted toclosely fit and move in an opening 43 in opening has therein thegrooves44, the use of which will be hereinafter explained. The outerauxiliary valve 40 has an enlarged head 45, which is adapted to beseated at certain valve 29.

47 designates air-passages in the valve 40, which register atcertaintimes with air-passages 48, which latter extend from the groove36 into the chamber 38, so as to allow the air back of the auxiliaryvalves 39 arid 40 to escape into the groove 36.

49 designates an air-passage leading from the groove 35 and opening intothe chamber 38 at a point just below the inner endof the valve 40, whenthe enlarged head thereof is seated in the recess 46, so that the valve39 will be seated at the bottom of the chamber 38 when the air passesthrough said passage into said chamber 38.

50 designates a passage through which the motive fluid passes to returnthe piston 34 and having the ports 51 and 52 opening into the interiorof the casing.

53 designates an exhaust-passage o ening into the interior of the casingat 54 an 55.

56 designates an exhaust-passage opening into the casing at 57, 58, and59, the port 58 with it the valve 20 secured thereto.

the piston is returned the dead air will all he exhausted and there willbe no compression of dead air between the piston and the valve 29. I

60 designates a passage through which the air passes to change the valveand having ports 61, 62, and 63 opening into the casing;

64 designates an exhaust port leading from-the in erior of the casing tothe atmos phere.

The 0 era-tion is as follows: Having the'i main Va ve 29 in the-positionseen in Fig. 1, 5 the trigger 25 is actuated and the spring- 1 pressedvalve-rod 19 will be depressed and 65 The pressure of the motive fluidagainst the valve 17 will hold the same firmly seated until the shoulder21 contacts with thebottom of the valve 17, at which time both valveswill be moved by the rod 19. As ,soon aa-the valve 20 begins to open thelive air will rush in and equalize the pressure, which will cause thevalve to be very easily regulated. If desired, the rod 18 may begrooved, at .at 18 so that a greater amount of air will passtherethrough. The parts being in the position seen in Figs. 1 and 5, themotive fluid now passes through passage 27 and port 28 into groove 35through port 52, passage 50, and port 51 underneath the piston and movesthe same rearward or toward the handle 7, the air back of the pistonexhaustingthrough ports 57 and 58 into. passage 56, through port 59,around the groove 36, and through the port 64 into'the air. The air willalso pass from the groove 35 through the passage 49 into the chamber 38and acting on the greater area 39 will cause the inner 'auxpressure ofthe air passing from the port 61 and passage 60 an through the per-t 63to the enlarged areas 31 and 45 until the piston contacts with thestriker or tappet 41, whereupon the inner auxiliary valve 39 will bemoved rearward into the posit-ion. seen in Figs. 2 and 3 and permit thelive air to enter through the passages 37, chamber 38, and grooves 42,and thus form a live-air cushion between the end of the piston and theadjacent endof the ;main valve 29. It will be observed that the ports 42terminate a short distance from the ends of the striker 41, so that whenthe latter reaches the position seen in Fi s. 2 and 3 a body of air istra ped between the piston and the juxtapose end of the main valve 29.The main valve 29 will now be moved rearward into the position seen inFig. 3, and the groove 35 will be out of register with the inletort28.The live air can now pass under t 10 main valve 29, the parts being inthe position seen in Fig. 3, and as I have a ncarly'straight or directand uninterrupted passage from the inlet in the handle to thepiston-chamber 33 the piston is driven forward with. great force and, Ia very powerful blow imparted to the shank -of the working tool 6. Asthepiston travgls forward the air in front of the piston Wlll 1 exhaustthrough port 54, passage 53, port 55,

annular groove 36 in the main valve 29, and port 64 to the air, sincethe mam valve is still in the position seen in Fig. 3; but as thepisbehind the valve, so that at the time the pistion impacts upon theworking tool the valve and its adjuncts will be firmly seated in theirforward position, as will be understood from Fig. It will be seen thatthe passages 47 of the outer auxiliary valve do not normallyre isterwith the passages 48 ofthe main va ve 29, which lead to the groove 36and thence to the exhaust-port 64 but if for any reason the mainvalve2-9 should stick in the cylinder so that the tool would not start theenlarged head 39 of the inner auxiliary valve would coact with the outerauxiliary valve 40 and raise-thelatter from its seat into the positionseen in Fig. 2, so.that the passages 47 and 48 would register with eachother and the air back of the valve escape around the groove '36 andthrough the exhaust-port 64 to the atmosphere.

' It is apparent that the casings 2 and 3 may be integral, if sodesired, and that slight changes may be made in the arrangement of" theports and assages, as well as the proporrions of the di erent areas ofthe valves, without departing from the spirit of my inventlon.

The motive fluid does not pass through the valve to move the pistonforward, and when the piston moves rearward there is-no compression ofthe exhausting air and the live air will enter with such rapidity that asufi'leient cushion will be formed to prevent the piston from everhitting the bottom of the main valve 29.

In the present embodiment of my invehtion I have shown the valvemechanism comprising the main valve and the inner and outer auxiliaryvalve as located directly within the extremity of the tool-cylinder; butit will be apparent that, if desired,

V changes therein within the scope of my inventio'n may be made. 1

It will be understood that while-I have shown in the present inventionthe preferred manner of arranging the ports and passages and haveomitted from some of the views for the sake of clearness ofillustrations certain ports and passages various othermodes of applyingthe principle of my invention may be employed for the mode hereinexplained, and various changes may therefore be made as regards themechanism thus disclosed, and I do not, therefore, desire to berestricted in everyv instance to the exact construction herein shown anddescribed.

Having thus described my invention,'what main valve, said valves movingin substantlal ahnement with said p1ston p i 2. In a pneumatic hammer avalve mechferential pressure areas, and a plurality of valves beingtappet-actuated;

3. In a pneumatic-hammer, a valve mechanism, comprising a main valve,and an inner and outer auxiliary valve, said outer valve being operatedby fluid-pressure, and said inner valve by its contact with the piston4. In a pneumatic hammer, a valve mechanism, comprising amain'valvehaving differential pressure areas,- an 'outer auxiliary valve havingdifferential ressure areas, and an inner auxiliary valve avingdifferential areas, said outer valve being operated by fluid-pressureand said inner valve by its contact with the'piston. V

5. In a pneumatic hammer, a valve mechanism, comprising a main valve,having dif outer auxiliary valve, said-outer valve bein operated byfluid-pressure, and a reduce end or striker on said inner valve, Whichlat,-

with.

anism, comprising a main valve having differential pressure areas and aninner and outer auxiliary valve, said outer valve having differentialpressure areas, air-passages extending from the rear of said outer valvethrough the smaller arealthereofi'and airpassages throughsaid main valvewith which outer valve isactuate inner valve being operated bycontact'with the piston, and .said outer valve by fluid-pressure. I

7. In a pneumatic-hammer, ,a valve mechanism, comprising 'a main valvehaving differential pressure areas, and an inner and outer auxiliar.valve, said outer valve havouter end of said main valve in which thelarger area of said outer valve is adapted to the seated,exhaust-passages through said main valve, and exhaust-passages throughsaid outervalve adapted to register therewith ated by fluid-pressure,and said inner valve i by contact with the piston.

8. In a pneumatic hammer, a valve mechanism; comprisinga main valve,having differential operated by. uid-pressure, said inner valve andmeans for exhausting theair from the larger area of the main valvethrough said outer valve and said main valve.

anism, comprising amain-valve and an inner and outer aux liary valve,said outer valve 'anism, comprising a main valve having dif inner andouter auxiliary valves, one of said a ter is operated by contact 'of'thepiston there- 6. In a pneumatic hammer, a valve meching diflerentiapressure areas, a'recess at the atcertain times, said outer valve beingoperferential pressure areas and an inner and said outer valve-passagesre(gister,when said sai IKO

ressure areas, and an inner and outer auxiliar valve,'sa1d outer valvebeing being operated by contactwith the :pistdn,

9. 'In a pneumatic hammer, avalve mech- 45 is open,

5 piston therein,

being operated by fluid- -ressure, said inner ,valve having differentiaareas, recesses in the smaller area thereof, air-passages through themain valve controlled by thelarger area 5 of said inner valve, wherebywhen the latter is actuated by contact with the piston, a liveaircushion is formed between the main valve and the piston, and a passagethrough the valve for live air which latter seats said inner valve.

- 10,411; a pneumatic hammer, a valve mechanism, comprising a main valvehaving differential areas and an inner and outer auxiliary valve, aninner and outer groove around r5 said main valve,- said inner groovecontroll theaclmisslon of air to return the "piston,

an 'saidputeI groovecontrolling the ex haust, said outer valve 'beingoperated by fluid-pressure'and said inner valve by conac tact-with thepiston.

1 1. -Ina pneumatic hammer, a valve mechamsm, comprising a mam valvehaving differential pressure arleas,- and an inner andouter auxiliaryvalve, each of said valves havdifferential pressure areas, sai& outer vave beingoperated by fluid -pressure, said inner'valve by its contactwith the piston, and inlet and-exhaust ports controlled by said mainvalve, said inlet-port when open permitting motive fluid to passdirectly to the piston-chamber without traversing said main valve;

12.111 a pneumatic hammer, a valve mech anism, comprising a main valve,and an inner 5 and outer auxiliary valve carried thereby,

each of said valves having differential pressure areas, said outer valvebeing operated byfluid-pressure, said inner valve beirg moved forwardlyby live air and rearwardly 40 by its contact with the piston, inlet andexhaust ports controlled by said main valve, exhaust-ports controlled bysaid outer valve, saidinlet-port admitting air to the cylinder undersaid main valve when said inlet-port and means for forming a live-aircushion between the piston and the adjacent end of said main valve.

13. In a pneumatic hammer, the combina tion of a cylinder and piston, avalve mechism, a tappet-actuated valve forming a part tween thepiston'and said main distributionvalve, whereby the latter is preventedfrom being damaged by said piston.-

15. In a pneumatic hammer, a cyl1nder,a

piston therein, a valve mechanism therefor,

said valve mechanism comprising a main distribution-valve, an outerauxiliary valve and an inner-auxiliary valve, means for admitting liveair to the piston to drive the latter forward without said airtraversing said valve mechanism, and means on said inner auxiliary valvefor creating a live-air cushion between the piston and main valve.

16. In apneumatic hammer, a cylinder adapted tojbe manually held andhaving a hammerin piston therein, the forward end of said cylinder beingadapted for the reception of the shank of'aworking tool, and a valvemechamsm for controlling the movement of-said piston and comprising amain valve'lo'cated in substantial alinement with said pistomand aninner and outer auxiliary valve carried by said main valve. H

17. In a pneumatic hammer, a cylinder adapted to be manually held andhaving a hammering-piston Y therein, the forward end of the latterbeingadapted for thereception of the shank of a working-tool, and a valvemechanism comprising a main valve having differential PTGSSUIGZHGES anda plurality of auxiliary valves'carried by said main valve.'

18. In a pneumatic hammer, a cylinder adapted to be manually held andhaving a hammering-piston therein, the forward end of the latter beingadapted for the reception of the shank of a working tool, a valvemechanismcomprising a main valve having differential pressure areas and'a plurality of auxiliary valves carried by said main valve, one of saidauxiliary valves being operated by fluid-pressure and the other by itscontact with said piston.

19. In thevalve mechanism of a pneumatic hammer, a tap et-actuated valvebeneath which motive uid'entersto actuate the piston and means actuatedby the tapp et tween the piston and valve mechanism.

20. In a. pneumatic hammer, a cylinder having a'hammering-pistontherein, a valve mechanism therefor comprising a main valve, and aninner and outer auxiliary valve carried thereby, said inner valve havinga striker 5 thereof for creating a live-air cushion be- IIO thereonoperated by contact of said piston therewith;

21. In a pneumatic hammer, a cylinder having a hammering-piston therein,a valve mechanism therefor comprising a main valve,

and an-inner and outer auxiliary valve car-.

ried thereby, said inner valve being operated,

by its contact with the piston, and means for exhausting the air fromthe larger area of the main valve through said outer valve and mainvalve.

22. Ina pneumatic hammer, a cylinder having a hammering-piston thereinand a valve mechanism therefor, comprising a main valve and a pluralityof auxiliary valves carried thereby, one of said auxiliary valves beingtappet-actuated and means controlled by the tappet for-creating alive-air cushion between said piston and valve mechanism.

23. In a pneumatic hammer, a cylinder, a piston therein and a valvemechanism there-' for comprising a main distribution-valve, anouterauxiliary valve, an inner auxiliary valve and a striker projecting fromthe latter through said main valve and having a groove thereinto permitthe creation of an air-cushion between said piston and main valve.

I 24. The combination of a cylinder having a hammering-piston therein, agrasping-handle on said cylinder, a manually-operated valve in saidhandle and a valve mechanism for said cylinder comprising a main valve,a

tappet-actuated inner auxiliary valve, an outer auxiliary valve andmeans actuated by the tappet for creating a live-air cushion betweensaid piston and valve mechanism.

25. In a pneumatic hammer, a cylinder having a hammering-piston thereinand an iliary valves being tappet-actutted, the other of said. auxiliaryvalves being fluid-actuated,

inlet-port, and a valve mechanism comprising a main valve controllingsaid port, and a plurality ofauxiliary valves, one of said auxand saidmain valve being above said inletport when in raised position. 26. In apneumatic hammer, a cylinder having a differential bore-provided with ahammering-piston, and a valve mechanism-- comprisinga main valveengaging said bore and having differential pressure areas, and aplurality, of auxiliary valves carried by said main valve, one of saidvalves being tappetactuated.

27. In a pneumatic hammer, a cylinder anism, comprising a main valve anda-plurality of inner and outer'auxiliary valves, the two latter beingarranged in alinement with each other.

i .JOHN 'F. CLEMENT. Witnesses: j

JOHN A. WIEDERSHEIM,

FAIRBANKS.

